Multichannel Decision Feedback Equalization in underwater sensor networks

Deepthi Chander (05407003)

Pallavi Manohar (05407002)

Features

Underwater acoustic channels-severely bandlimited Multipath –challenging issue Digital transmission-multipath causes ISI Multichannel equalizer-exploits spatial diversity of

multipath Decision Feedback Equalizer (DFE) removes ISI

from previously estimated symbols Phase synchronization and equalization performed

jointly-Recursive least Squares (RLS) algorithm used for fast convergence

Phase Coherent Multichannel Decision Feedback Equalizer (DFE)

feedforwardfilter 1x

1/Ts 1/T

Carrier

correction1

Input 1

feedforwrdfilter Kx

1/Ts 1/T

Carrier

correction K

Input K

.

.

.Σ + Symbol

decision

feedbackfilter

-

Estimated symbol

AdaptiveAlgorithm (RLS)

2nd order PLL Training symbol

+-

error

THANK YOU

Reduced Complexity Multichannel DFE

x1/Ts

Carrier

correction1

Input 1

x1/Ts

Carrier

correction K

Input K

.

.

.

Estimated symbol

Spatialpre-combiner

Multichannel DFE